Joel Cuello has fond memories of the small patch of dirt behind the elementary school he attended in the Philippines. Textbook lessons on germination and photosynthesis came to life as the students sowed seeds that sprouted into plants. He and his classmates learned the importance of light, carbon dioxide, water and nutrients on the plants' growth, and they saw the connection between plants and food as they harvested their crops.

No one could have guessed those early lessons in the garden would cultivate a lifelong passion. As a professor of agricultural and biosystems engineering at the University of Arizona, Cuello still grows plants in a tiny space on campus, but with a larger purpose in mind. He wants to feed the world.